mirror of https://gitee.com/openkylin/linux.git
d8d5900ef8
Jan Beulich points out that vmalloc_sync_all() assumes that the kernel's pmd is always expected to be present in the pgd. The current pgd construction code will add the pgd to the pgd_list before its pmds have been pre-populated, thereby making it visible to vmalloc_sync_all(). However, because pgd_prepopulate_pmd also does the allocation, it may block and cannot be done under spinlock. The solution is to preallocate the pmds out of the spinlock, then populate them while holding the pgd_list lock. This patch also pulls the pmd preallocation and mop-up functions out to be common, assuming that the compiler will generate no code for them when PREALLOCTED_PMDS is 0. Also, there's no need for pgd_ctor to clear the pgd again, since it's allocated as a zeroed page. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: xen-devel <xen-devel@lists.xensource.com> Cc: Stephen Tweedie <sct@redhat.com> Cc: Eduardo Habkost <ehabkost@redhat.com> Cc: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Jan Beulich <jbeulich@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> |
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| .. | ||
| Makefile | ||
| discontig_32.c | ||
| dump_pagetables.c | ||
| extable.c | ||
| fault.c | ||
| highmem_32.c | ||
| hugetlbpage.c | ||
| init_32.c | ||
| init_64.c | ||
| ioremap.c | ||
| k8topology_64.c | ||
| mmap.c | ||
| numa_64.c | ||
| pageattr-test.c | ||
| pageattr.c | ||
| pat.c | ||
| pgtable.c | ||
| pgtable_32.c | ||
| srat_64.c | ||